1. Field of the Invention
The invention is related in general to removable media cartridges, such as tape, optical, DVD, flash memory, or hard disk drive cartridges. More particularly, the invention consists of a generally cylindrically shaped rotary switch which is at an acute angle to two planes of the removable media cartridge or a generally cone shaped rotary switch which is perpendicular to a plane of the removable media cartridge, so that the switch can be simultaneously read by two disparate system components.
2. Description of the Prior Art
Storage automation products, such as the IBM 3584 Ultra Scalable Tape Library, provided by International Business Machines (“IBM”)®, include removable media such as tape cartridges, one or more robotic accessors (“pickers”), one or more devices for reading from and writing to the removable media such as tape drives, and a plurality of storage cells for holding the removable media. Typically, removable media include a switch that indicates whether the media can be written to or if the media has been designated as write-protect. This switch is usually accessed by a component of the tape drive.
A static switch, such as a single flat surface, can provide only a limited amount of information, as dictated by the physical dimension of the flat surface. It is desirable to increase kinds and amount of information that may be contained on a switch. Therefore, it is desirable to increase the surface area of a switch in order to increase the amount of information that may be obtained. Accordingly, it is desirable to have a non-static switch that can dynamically provide information related to the removable media.
In U.S. Pat. No. 5,859,755, Griffin et al. disclose a rotary switch that rotates about an axis. This rotary switch allows for the dynamic display of information on a dynamic display surface. As taught by Griffin, the surface of the switch is parallel to the plane of the tape. Other devices, such as pickers, may also need information from the switch. These devices may reside in a plane other than the tape drive interrogator. Accordingly, it is desirable to have a surface of a switch for displaying information that may be simultaneously read by more than one device residing in more than one plane.
In U.S. Pat. No. 6,772,430, Oishi et al. disclose a rotary switch with a surface which is simultaneously accessible by two different components residing in two different planes. However, Oishi teaches that these two components are an optical source and a photodetector which are orthogonal to each other. Light travels from the source to the display surface and to the target (photodetector). However, it is desirable for two devices to simultaneously access the surface. To facilitate this, it would be desirable to have two disparate surfaces, each facing its respective interrogative device. Additionally, it would be desirable to have these surfaces perpendicular to their corresponding devices.